1. Field of the Invention
The present invention relates to an arrangement for mechanically coupling an overload relay to a contactor. More specifically, the present invention relates to an arrangement wherein the overload relay comprises at least one protruding hook which is inserted into a coupling cutout located at a contactor housing and which has a latch element molded onto at least one of two sides facing away from each other on a flat end section of the hook, and wherein the overload relay supports at least one protruding electrically conductive connection pin which is inserted into a connection terminal of the contactor and is retained therein.
2. Description of Related Art
EP-A1-0774768 describes an arrangement for mechanically and electrically coupling an overload relay to a contactor. In this arrangement, the overload relay is equipped with flexible, deformable hooks, whose latch elements latch into and behind rims of orifices in a housing of the contactor. Rigid, electrically conductive connection pins of the overload relay are inserted into the connection terminals of the contactor and are clamped into place therein.
As a result, in this arrangement, the bending moment that occurs during operation must be absorbed by the connection terminals alone. The flexible, deformable hooks do not relieve the connection terminals during a bending moment load. In this fashion, the mechanical and electrical connection between the overload relay and the contactor in this arrangement is secured.
In practice, a choice exists between connection terminals that have wire cages and connection terminals that have pressure plate claws. With the wire cages, the connection pin of the overload relay is pulled up to the connection piece of the contactor from below. In contrast, with pressure plate claws, the connection pin is pushed down to the connection piece of the contactor from the top. The two types of coupling therefore result in different relative heights between the overload relay and the contactor. For this reason, the flexible deformable hooks on the overload relay must be at different heights for the two types of connection terminals. This, however, makes it necessary to manufacture two different types of overload relays and to maintain an inventory of both types.